From: Mikko Rasa <tdb@tdb.fi>
Date: Tue, 2 Nov 2021 10:17:24 +0000 (+0200)
Subject: Support loading raw texture data from an external file
X-Git-Url: http://git.tdb.fi/?p=libs%2Fgl.git;a=commitdiff_plain;h=b274dc87db4422498e72823649358114dfca0096

Support loading raw texture data from an external file

This enables async loading of pixel formats not supported by standard
image files.
---

diff --git a/source/backends/opengl/texture2d_backend.cpp b/source/backends/opengl/texture2d_backend.cpp
index 9efc4351..578cefe3 100644
--- a/source/backends/opengl/texture2d_backend.cpp
+++ b/source/backends/opengl/texture2d_backend.cpp
@@ -1,3 +1,4 @@
+#include <msp/datafile/rawdata.h>
 #include <msp/gl/extensions/arb_direct_state_access.h>
 #include <msp/gl/extensions/arb_texture_storage.h>
 #include <msp/gl/extensions/arb_vertex_buffer_object.h>
@@ -7,6 +8,8 @@
 #include "texture2d.h"
 #include "texture2d_backend.h"
 
+using namespace std;
+
 namespace Msp {
 namespace GL {
 
@@ -19,6 +22,7 @@ private:
 	char *mapped_address = 0;
 	Graphics::Image image;
 	Graphics::ImageLoader *img_loader = 0;
+	DataFile::RawData *raw_data = 0;
 	unsigned n_bytes = 0;
 	int phase = 0;
 
@@ -105,15 +109,27 @@ void OpenGLTexture2D::unload()
 
 OpenGLTexture2D::AsyncLoader::AsyncLoader(Texture2D &t, IO::Seekable &i):
 	texture(t),
-	io(i),
-	img_loader(Graphics::ImageLoader::open_io(io))
-{ }
+	io(i)
+{
+	char magic[4] = { };
+	io.read(magic, 4);
+	io.seek(0, IO::S_BEG);
+
+	if(DataFile::RawData::detect_signature(string(magic, 4)))
+	{
+		raw_data = new DataFile::RawData;
+		raw_data->open_io(io, "async");
+	}
+	else
+		img_loader = Graphics::ImageLoader::open_io(io);
+}
 
 OpenGLTexture2D::AsyncLoader::~AsyncLoader()
 {
 	if(mapped_address)
 		pixel_buffer.unmap();
 	delete img_loader;
+	delete raw_data;
 }
 
 bool OpenGLTexture2D::AsyncLoader::needs_sync() const
@@ -125,8 +141,13 @@ bool OpenGLTexture2D::AsyncLoader::process()
 {
 	if(phase==0)
 	{
-		image.load_headers(*img_loader);
-		n_bytes = image.get_stride()*image.get_height();
+		if(raw_data)
+			n_bytes = raw_data->get_size();
+		else
+		{
+			image.load_headers(*img_loader);
+			n_bytes = image.get_stride()*image.get_height();
+		}
 	}
 	else if(phase==1)
 	{
@@ -134,7 +155,12 @@ bool OpenGLTexture2D::AsyncLoader::process()
 		mapped_address = reinterpret_cast<char *>(pixel_buffer.map());
 	}
 	else if(phase==2)
-		image.load_into(*img_loader, mapped_address);
+	{
+		if(raw_data)
+			raw_data->load_into(mapped_address);
+		else
+			image.load_into(*img_loader, mapped_address);
+	}
 	else if(phase==3)
 	{
 		mapped_address = 0;
@@ -147,10 +173,13 @@ bool OpenGLTexture2D::AsyncLoader::process()
 		if(!texture.id)
 			texture.create();
 
-		unsigned w = image.get_width();
-		unsigned h = image.get_height();
-		texture.storage(pixelformat_from_image(image, texture.use_srgb_format), w, h);
-		texture.OpenGLTexture2D::sub_image(0, 0, 0, w, h, pixel_buffer, 0);
+		if(img_loader)
+		{
+			unsigned w = image.get_width();
+			unsigned h = image.get_height();
+			texture.storage(pixelformat_from_image(image, texture.use_srgb_format), w, h);
+		}
+		texture.OpenGLTexture2D::sub_image(0, 0, 0, texture.width, texture.height, pixel_buffer, 0);
 
 		if(texture.auto_gen_mipmap)
 			texture.generate_mipmap();
diff --git a/source/core/texture.cpp b/source/core/texture.cpp
index 175e76a2..5f21229f 100644
--- a/source/core/texture.cpp
+++ b/source/core/texture.cpp
@@ -1,3 +1,4 @@
+#include <msp/datafile/rawdata.h>
 #include <msp/io/memory.h>
 #include "error.h"
 #include "resourcemanager.h"
@@ -87,6 +88,7 @@ Texture::Loader::Loader(Texture &t, Collection *c):
 	CollectionObjectLoader<Texture>(t, c),
 	levels(0)
 {
+	add("external_data", &Loader::external_data);
 	add("external_image", &Loader::external_image, false);
 	add("external_image_srgb", &Loader::external_image, true);
 	add("generate_mipmap", &Loader::generate_mipmap);
@@ -109,6 +111,19 @@ void Texture::Loader::load_external_image(Graphics::Image &img, const string &fn
 	img.load_io(*io);
 }
 
+void Texture::Loader::external_data(const string &fn)
+{
+	if(obj.manager)
+		obj.manager->set_resource_location(obj, get_collection(), fn);
+	else
+	{
+		DataFile::RawData rd;
+		rd.open_file(get_collection(), fn);
+		rd.load();
+		obj.image(0, rd.get_data());
+	}
+}
+
 void Texture::Loader::external_image(bool srgb, const string &fn)
 {
 	obj.use_srgb_format = srgb;
diff --git a/source/core/texture.h b/source/core/texture.h
index 8db5dad8..639b15f5 100644
--- a/source/core/texture.h
+++ b/source/core/texture.h
@@ -49,6 +49,7 @@ protected:
 		void load_external_image(Graphics::Image &, const std::string &);
 
 	private:
+		void external_data(const std::string &);
 		void external_image(bool, const std::string &);
 		void generate_mipmap(bool);
 		void image_data(const std::string &);